The present disclosure relates to shading correction in a digital microscope apparatus.
In a digital microscope apparatus, it is important to appropriately perform shading correction when a pathological image is acquired from a pathological slide (preparation PRT). In order to appropriately perform shading correction, it is important to appropriately capture, for shading correction, an image in which a biological sample SPL is not photographed (hereinafter, referred to as entirely-white image or white image).
As a method of capturing an entirely-white image when performing shading correction, a method of acquiring an entirely-white image in which all unevenness factors of a light source, an illumination optical system, and an imaging optical system are superimposed by capturing an entirely-white image without disposing a sample on a stage is disclosed (see, for example, Japanese Patent Application Laid-open No. 2011-124948).
Moreover, in order to prevent the contrast of a pathological image of a pathological slide captured by a digital microscope apparatus from inappropriately decreasing, an illumination optical system should be appropriately in focus.
In this regard, there exists a technique in which a phase difference autofocusing (AF) is used to automatically and appropriately allow an illumination optical system to be in focus (see, for example, Japanese Patent Application Laid-open No. 2012-008450).